When we are young, our brains can recall specific events and experiences, but as we age, our ability to ignore or filter out irrelevant information weakens, resulting in an overload of information that clutters our memories, according to a new study that reviews more than 20 years of research.
This clutter makes retrieving specific or targeted information such as when or where an event occurred more difficult – other trivial memories and details are pulled up as well – which may explain why our memory becomes more impaired as we age, researchers say.
At the same time, the excess information could also explain a paradox in aging – the notion that adults acquire wisdom and knowledge with age even as our memory diminishes, according to the paper, which looked at both behavioural and neuroimaging studies and was published in the journal Trends in Cognitive Science last week.
“When older adults try to remember one particular detail, they experience more difficulty because that one detail has become connected to all sorts of other details in their mind, and they need to filter through them all,” said Dr. Lynn Hasher, the co-author of the study and a senior scientist with Rotman Research Institute at Baycrest Centre for Geriatric Care in a statement.
The upside, however, is that older adults may be better at using all that information to make decisions and when engaging in something more creative, the authors suggested, while acknowledging that more study was needed in this area.
“In research labs, we tend to focus on precision of memory, but in real life, precision hardly matters. As researchers, we may be overestimating the disadvantage that older adults have with theixjmtzywr memory and underestimating the advantages,” Hasher said.
Some of the behavioural studies reviewed illustrated how older adults can use the excess information they collected to help them find solutions to their problems. At the same time, this over-reliance on previous knowledge can also result in memory errors, such as recalling false memories, the authors, which also include researchers with Columbia and Harvard University, wrote in the paper.
The review of studies showed that, unlike older participants who stored inconsequential information, younger adults suppressed them. Brain activity measured through neuroimaging appeared to show similar results.
“Although we use the term ‘cluttered’ to capture the nature of older adults’ memory representations, they could also be described as ‘enriched’, ‘elaborated’, or ‘overloaded’,” researchers wrote.
“There might also be treasure in the clutter that can support other memory-dependent cognitive functions. In other words, the clutter of irrelevant information might interfere with target memory retrieval in one context, but might also provide surprising advantages in other tasks or contexts that benefit from extraneous knowledge.”
The authors suggest that further research could explore new ways to improve memory and learning in older adults by leveraging the excess information or “distractions.”
